Design

Kill! Kill them all! Drive them to extinction! Only when they are all dead can we be safe!

Such violent thoughts consumed Huo Gu's mind and spread from his consciousness to every single-celled organism. Like soldiers receiving orders, the cells went from resisting under Huo Gu's control with enzymes to fighting on their own. The moment a bacteriophage parasitized one of them, it immediately committed suicide, sealing its cell membrane and perishing together with the bacteriophage.

The mutations in the single-celled organisms instantly broke the stalemate. Huo Gu's cluster of cells began gaining the upper hand, pushing back over the corpses of their companions.

When the last bacteriophage died to a single cell's suicidal attack after parasitizing it, the desperate battle finally came to an end.

Corpses lay everywhere. Even surrounded by endless darkness, Huo Gu could roughly picture the scene. By then, the single-celled cluster had shrunk to one-twentieth of its original size.

Once he calmed down, Huo Gu felt a lingering chill of fear. If he still had a human body, he would probably have felt as though he had been soaked in ice water.

If there had been even twice as many bacteriophages in that battle just now, it would have been over...

"No. I have to find the cause of the double-walled cells' deaths immediately!"

Huo Gu quickly shifted his attention to the double-walled cells, which had already died out completely.

"First, I need to eliminate the impossible factors one by one..."

"It can't have been things like antibiotics. Fungi and bacteria may be able to produce them, but viruses like bacteriophages cannot. Their structures are too simple. Besides, if it had originated from the single-celled organisms themselves, then the double-walled cells should have had some degree of resistance..."

"Then what caused it?"

Huo Gu realized he had returned to the original question—how had the double-walled cells died?

"First of all, when they had a single wall, they were perfectly fine..."

"Wait, single-walled? That's right, single-walled!"

Huo Gu suddenly understood. Thinking of something, he sharply focused his attention on the slightly staggered tunnel.

Because of that staggered arrangement, the tunnel had formed a channel for material exchange that was wide at both ends and narrow in the middle.

Originally, it had been meant to allow the single-celled organisms to exchange matter, energy, and information with the outside world. These were things every living organism absolutely needed to sustain its activities.

Now, this tunnel was blocked, plugged by molecular clusters both small and large.

It was like completely blocking a person's mouth and nose. The death of the double-walled cells was only natural.

"So this was a design flaw from the very beginning. But what should I do? Even if I alter the DNA, there's no way to solve the blockage problem. If I give up narrowing the tunnel, then I won't be able to defend against those damned bacteriophages at all."

His train of thought gradually entered a dead end. After a while, Huo Gu's thoughts had become a complete muddle, and he could not think of any good solution.

"Maybe I should try a different approach..."

Since this path would not work, he might as well take another. Huo Gu's thoughts flashed back to the battle against the bacteriophage swarm.

"I am not I, but we..."

"An individual's abilities are limited, after all. Maybe I should work in this direction..."

A vague outline gradually emerged in Huo Gu's mind—multicellular life!

"For skin, the outermost cells will do. Make them completely sealed cells, and leave the task of sustaining life to the inner cells protected by this layer of 'epidermis.'"

A long, bamboo-like organism appeared before Huo Gu.

"The inner cells will only be responsible for transporting nutrients. Defense and attack will be left to other types of cells."

"There should preferably be an internal space as well, making targeted attacks easier."

The elongated organism in his mind turned transparent, revealing the structure Huo Gu had envisioned. The inner walls of the cavity were lined with surface cells identical to the outer skin. When microorganisms entered the cavity, these epidermal cells within it would release large amounts of enzymes, breaking down the microorganisms into amino acids.

That way, the cavity would become a completely harmless nutrient solution. Although it contained large amounts of enzymes, as long as the cell walls of the epidermal cells inside the cavity were maintained and the two sides remained balanced, the "digestive fluid" within the cavity would be harmless.

"It will involve two openings. When the entire single-celled cluster moves, the flowing water itself will carry those microorganisms into the cavity."

At that moment, Huo Gu's thoughts suddenly halted. He had discovered a problem.

How would it absorb the amino acids broken down by the enzymes?

This was a critical problem. If it could not take in the amino acids inside the cavity, then all the previous designs would have been wasted effort.

Was there really no solution? Huo Gu fell into thought once more, searching through his memories from his time as a human for biological designs recorded in books.

"What about humans?"

"How do humans absorb nutrients after eating?"

Huo Gu asked himself.

"The gastric mucosa. The gastric mucosa is alkaline and can neutralize stomach acid, so stomach acid does not threaten the stomach—unless the gastric mucosa is damaged..."

"I can try formulating an inhibitor for the enzymes used as 'digestive fluid.' That way, I won't need to worry about the enzymes breaking down the cavity walls."

"Then the cell walls of the epidermal cells lining the cavity won't be necess—"

Huo Gu's thought suddenly stopped, and he immediately dismissed the idea.

"No, they still have to be there. What if those microorganisms complete their infection and parasitization of the cells inside the cavity before they are digested?"

This was an issue that had to be considered. Huo Gu decided to retain the original cell wall design for the cells inside the cavity.

Next came the design for "opening" and "closing" the mouth.

This was not especially difficult. There were already protein structures that could serve as "ropes," allowing it to imitate the "tendons" of multicellular organisms.

Although there were no muscle fibers to provide force, that did not matter. Cell division could fully provide the driving force.

The only drawback was that it would never be able to open and close its mouth as quickly as multicellular organisms with muscle fibers.

However, Huo Gu was not worried about this weakness, because the opponents it would face were microorganisms. The speed at which it opened and closed its mouth did not matter much.

It could be said that as long as it was not fighting multicellular organisms, Huo Gu's design would be invincible. Even against that previous swarm of bacteriophages, he was confident it could crush them.

The situation was no longer like before, when each cell fought on its own, scattered like loose sand. With this design, the single-celled cluster would be like a clenched fist, capable of destroying any microorganism that dared throw a punch at it.

In terms of size, the microorganisms had lost from the very beginning.